Perhaps I just don't know how underpowered the processor
is
on that tablet. LOL

I think you'll find that that is the reason. You said it earlier I believe, that you know that an iPad isn't a PC (or words to that effect) yet it seems to me to be determined to do edits on an iPad !

I'm coming at the iPad with a different simpler requirement - and for that I'd go for PhotoSmith - I simply want to look at my images on my iPad, in order to rate/flag/decide which are keepers etc. So I have that app, and so far because I'm new to iPads (though very computer literate) and Apple, I'm finding image transfers to be a very frustrating exercise.

I have Lightroom 3.6 and 4 - be AWARE (which I'm sure you probably are) that applications like PhotoSmith transfer images WIRELESSLY to your computer (yes, even if you stick the iPad cable into both it and your PC !).

I found this out when it took me over 1hour to put just 47 Photosmith'ed images from my iPad into Lightroom..... (12mp raw files) and Photosmith support confirmed that this is how transferring files across works (due to Apple restrictions). There is an 'advanced' way of importing said images into Lightroom via the cable, but for me, so far it doesn't work.

(though I've just come onto this forum area with this issue so a search on here may prove fruitful in finding a solution)